1. Field of the Invention
The present invention relates to a slot array antenna and a plasma processing apparatus using the same. The slot array antenna or the plasma processing apparatus according to the present invention is suitably applicable, in particular, to a plasma processing apparatus using a rectangular-type antenna (e.g., a plasma processing apparatus to be used for manufacturing liquid crystal devices).
2. Related Background Art
The slot array antenna and plasma processing apparatus according to the present invention is generally applicable to general plasma processing procedures, including the production of materials for electronic devices such as semiconductors or semiconductor devices, and liquid crystal devices. For the convenience of explanation, however, only the background art relating to liquid crystal devices will be described here.
In general, the process for manufacturing liquid crystal devices involves subjecting a base material (such as wafer) to various kinds of treatments such as CVD (chemical vapor deposition), etching, and sputtering. A plasma processing apparatus has often been used for conducting such treatments. This is because, when a plasma processing apparatus is used, a substrate can be processed if the substrate is maintained at a low temperature.
(Patent Document 1)
JP-A (Japanese Unexamined Patent Publication) No. 2000-123997
The above-mentioned JP-A No. 2000-123997 (Patent Document 1) discloses a plasma processing apparatus, which may be used for manufacturing liquid crystal devices. In such a plasma processing apparatus, use of a slot array antenna is considered to be very promising and highly efficient antenna having a small transmission loss. Particularly promising is an apparatus having a single layer structure (wherein a power feeding waveguide is disposed in the same plane as a radiating waveguide) capable of permitting easy formation of an antenna structure, wherein power is supplied to the radiating waveguide via a window provided in the wall of the power feeding waveguide.
However, according to the present inventors' experiments, it has been found that, when using a conventional plasma processing apparatus having the above-mentioned structure, it is difficult to increase the plasma density in the plasma processing chamber.